From 1159a193696ad48ec86e5895f6dee3e539619c0e Mon Sep 17 00:00:00 2001 From: Will Newton Date: Mon, 12 Aug 2013 15:08:02 +0100 Subject: malloc: Check for integer overflow in pvalloc. A large bytes parameter to pvalloc could cause an integer overflow and corrupt allocator internals. Check the overflow does not occur before continuing with the allocation. ChangeLog: 2013-09-11 Will Newton [BZ #15855] * malloc/malloc.c (__libc_pvalloc): Check the value of bytes does not overflow. --- malloc/malloc.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'malloc/malloc.c') diff --git a/malloc/malloc.c b/malloc/malloc.c index dd295f522c..7f43ba3b8f 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -3082,6 +3082,13 @@ __libc_pvalloc(size_t bytes) size_t page_mask = GLRO(dl_pagesize) - 1; size_t rounded_bytes = (bytes + page_mask) & ~(page_mask); + /* Check for overflow. */ + if (bytes > SIZE_MAX - 2*pagesz - MINSIZE) + { + __set_errno (ENOMEM); + return 0; + } + void *(*hook) (size_t, size_t, const void *) = force_reg (__memalign_hook); if (__builtin_expect (hook != NULL, 0)) -- cgit 1.4.1